PCalc has always been the best calculator app on iOS, and as with all iOS version updates before, it is ready on day one. PCalc works really well with iOS 10. The app looks great and fits right in with iOS, while retaining a distinct character of its own.
There is a new today widget for quick calculations, taking full advantage of the changes in iOS 10
The ability to customize the buttons of the calculator to your own needs is a great feature which makes PCalc stand out from other calculator apps. Not only is this extremely useful but also executed very very well.
As I already wrote for the iOS 7, 8 and 9 updates, this could have easily been a paid upgrade, and frankly I believe this is overdue. I myself have definitely already gotten a lot more than my moneys worth out of this app.

This is not just a calculator. Its a masterpiece of Software sweating details others never think about, details most never see or use but they are there. The developer just cares about all that alone is worth it.

If you want to add 1 + 1, the built-in iPhone calculator will do you fine. If you want do the kind of math that matters -- build things, develop things, define things -- then you need a serious calculator for serious work. PCalc is all that and more. Toss your old HP, and let your PCalc for iPhone do your figuring.

I love having a fully functioning scientific calculator in my pocket. The developer is sooo responsive too. I suggested a 1/x function, explained why it would be a good idea and shortly thereafter it was included in the free version. Then i bought the full version. Worth the $10 to me at least. Thanks a 10 exp6